Field of the Disclosure
Embodiments of the invention relate to a display device, and more particularly, relate to a display device and a method of driving the same that can reduce 3D (three-dimensional) crosstalk while displaying a 3D image when the device uses a parallax barrier or lenticular lens having a slanted structure.
Discussion of the Related Art
Imaging technology creating a 3D effect from 2D (two-dimensional) images influences not only display devices but also other fields such as home appliances, telecommunications, aerospace, automotive, and fine arts. The effect of the 3D technology in the market is expected to be greater than that of HDTV.
Of the factors with which a human being perceives a 3D effect, a binocular parallax is most important, but mental and memory factors are closely associated. Accordingly, 3D imaging technology is categorized into a depth image type, a 3D image type, and a stereographic image type with respect to what extent 3D image information is supplied to a viewer.
Among these types, the depth image type is a method of providing depth perspective using a mental factor and a draw-in effect, and is applied to a 3D computer graphic that displays perspective, overlap, shadow, light and shade, movement, and the like by calculation. For example, an I-MAX movie which supplies a wide-view large-sized screen to a viewer can create an optical illusion of image depth with respect to the projection screen. The 3D image type known as the perfect one of the 3D imaging technologies is a holographic type such as a laser beam reproduction holograph or a white light reproduction holograph.
However, because the above depth image type or holographic 3D image type have limitations of high cost, high equipment expense, and high data requirements to increase spatial depth perception, the stereographic type using a physiological factor with both eyes is widely used.
The stereographic type display device displays a 3D image using binocular parallax. In this 3D imaging type, when the right and left eyes of a viewer that are spaced apart from each other at about 65 mm look at two respective 2D images, the two 2D images are processed by the brain mixing the two 2D images. Thus, a 3D image having depth is perceived. The stereographic type display device is categorized into a glasses-type in which a viewer wears glasses, and a non-glasses type that uses a lens array such as a parallax barrier, lenticular lens, or the like, so the user does not need glasses. Among these, the non-glasses type is preferable.
Particularly, among the non-glasses type display devices, a parallax barrier-type is preferable.
FIG. 1 is a schematic cross-sectional view illustrating a parallax barrier-type 3D display device according to the related art. FIG. 2 is a schematic plan view illustrating a barrier panel of a vertical structure according to the related art. And, FIG. 3 is a schematic plan view illustrating a barrier panel of a slanted structure according to the related art.
Referring to FIG. 1, the 3D display device 10 includes a display panel 20, and a barrier panel 30 on a front of the display panel 20.
The display panel 10 includes a plurality of pixels P in a matrix. Pixels R for right eye (i.e., right-eye pixels) and pixels L for left eye (i.e., left-eye pixels) are alternately arranged in a horizontal direction.
Referring to FIG. 2, the barrier panel 30a of the vertical structure includes alternating barrier regions B that block light and transmissive regions T that transmit light. The barrier regions B and the transmissive regions T extend in a stripe pattern in a vertical direction.
When the barrier regions B are patterned in the vertical direction, 2 views displaying one image for left eye (i.e., an left-eye image) and another image for right eye (i.e., a right-eye image), respectively, are alternately produced at the front of the barrier panel 30a. In this case, a 3D image can be perceived.
However, the vertical structure-type barrier panel 30a causes too much flicker.
Referring to FIG. 3, the slanted structure-type barrier panel 30b includes barrier regions B and transmissive regions T extending in a slanted direction with respect to the vertical direction.
In this case, a pixel group having 3 pixels or more of the display panel 20 is arranged repeatedly in a slated direction corresponding to the barrier region B.
Because of the slanted barrier structure and pixel structure, 3 or more multi-views corresponding to a number of pixels of the pixel group and displaying a left-eye image and a right-eye image are produced that overlap one another in front of the barrier panel 30b. In this case, when a viewer's left and right eyes are positioned at the 2 views out of the multi-views, a 3D image can be perceived.
Perceived flicker of the display device using the slanted structure-type barrier panel 30b is reduced compared to that with a vertical structure barrier.
However, the slanted structure-type barrier panel 30b causes 3D crosstalk (C/T). In other words, the left-eye image and the right-eye image deviate from a limit acceptable area of a barrier pitch affecting the right eye and the left eye. This image deviation causes crosstalk.
It is commonly understood that the area of the transmissive region T can be increased to increase output luminance of the display device. However, referring to FIG. 4 and Table 1, when an open ratio of the transmissive region T (i.e., an open ratio) to the barrier region B (i.e., a light blocking region) becomes more than a predetermined ratio, the 3D C/T increases rapidly, and this is a limitation on increasing luminance.
TABLE 1Open ratio  25%33.3%41.7%  50%3D C/T4.13%4.36%5.88%11.49%
Accordingly, reduction of the 3D C/T is required for the 3D display device using the slanted structure-type barrier panel 30b. 
Also, a 3D display device using a slanted structure lenticular lens has the 3D C/T similar to the 3D display device using the slanted structure barrier panel. Therefore, reduction of the 3D C/T is also required for the 3D display device using the slanted structure lenticular lens.